Investigation of the Appropriate Formulation of Magnesium Oxide Powder for One-dose Package

Abstract

Magnesium oxide tablets are sometimes crushed prior to administration to patients having difficulties in swallowing tablets. However, the quality of magnesium oxide formulations may decrease when stored for a long time as a one-dose package, owing to the absorption of high amounts of moisture by magnesium oxide. Additionally, as magnesium oxide solution is alkaline, it can interact with other medicines, making it incompatible for one-dose packaging. There are three types of magnesium oxide powder formulations: crushed magnesium oxide tablets, magnesium oxide bulk powder, and magnesium oxide granules. However, the appropriate formulation of magnesium oxide for one-dose packages is unknown. The stability of powder formulations stored as one-dose packages at 75 RH for 3 months was evaluated by analyzing the change in weight change and dissolution. The dissolution of the three powder formulations did not change for 3 months. Although the weight had increased in all the formulations, the change in the weight of magnesium oxide granules was the lowest among the three formulations. Isoniazid and levodopa tablets have been reported to interact with magnesium oxide tablets. The incompatibility between the crushed powder of these medicines and magnesium oxide powder formulations was analyzed when stored as one-dose packages. Among the three formulations, incompatibility was the lowest for granule. In conclusion, preserving magnesium oxide and other formulations that causes incompatibility should basically be avoided. However, magnesium oxide granules can be used for storing with the other formulations that interact with magnesium oxide within a term to circumvent incompatibility.